Endoscopic ultrasound-guided biliary drainage as an alternative to percutaneous drainage and surgical bypass

Table 1 Advanvtage and disadvantage of puncturing sites

Route of access
Extrahepatic route	Intrahepatic route
Easy approach (especially for large-caliber CBD) The puncture site is close to the scope More difficult scope positioning to achieve desired direction from the punctured duct (rendezvous) Easy guidewire negotiation and neo-tract creation (EUS-BD) Difficult scope handling	The duct to be punctured is far from the scope Easier scope positioning to achieve desired direction from the punctured duct Easy scope handling Difficult guidewire negotiation and neo-tract creation Higher risk of bleeding Higher risk of bile leakage

CBD: Common bile duct; EUS-BD: Endoscopic ultrasound guided biliary drainage.

Table 2 Compare the two neo-tract creation methods

Neo-tract creation methods
Cauterization	Non-cauterization
Easy neo-tract creation with no need for forceful manipulation More tissue injury from thermal burn The procedure takes less time More complications, especially bile leakage or perforation	More difficult and forceful manipulation, especially when the intervening tissue is thick or the direction is inappropriate Less injury, smaller diameter of the neo-tract Lower risk of bile leakage or bleeding

Table 3 Compare the two neo-tract dilation methods

Dilatation methods
Balloon dilation	Graded dilation
Radial force leads to bigger neo-tract diameter (easier but greater risk for bile leakage, bleeding and perforation)	Axial force creates a smaller neo-tract. More difficult, but less leakage and less bleeding)
Easier stent insertion	Stent insertion can be more difficult
Only a single dilation session is needed and there are fewer guidewire exchanges	More sessions of dilation are needed and there are more frequent guidewire exchanges